Oracle数据库-行转列（动态行转不定列)

/*物料 需要数量 需要仓库 现存量仓库 现存量仓库数量 批次 
A1 2 C1 C1         20         123 
A1 2 C1 C2         30         111 
A1 2 C1 C2         20         222 
A1 2 C1 C3         10         211 
A2 3 C4 C1         40         321 
A2 3 C4 C4         50         222 
A2 3 C4 C4         60         333 
A2 3 C4 C5         70         223 
我需要把上面的查询结果转换为下面的。
物料 需要数量 需要仓库 C1 C2 C3 C4 C5 
A1 2 C1 20 50 10 0 0 
A2 3 C4 40 0 0 110 70 
*/ 
---------------------------------------------------------------建表
----------------判断表是否存在
declare num number; 
begin 
    select count(1) into num from user_tables where table_name='TEST';
    if num>0 then 
      execute immediate 'drop table TEST';
    end if;
end;
----------------建表
CREATE TABLE TEST(
    WL VARCHAR2(10),
    XYSL INTEGER,
    XYCK VARCHAR2(10),
    XCLCK VARCHAR2(10),
    XCLCKSL INTEGER,
    PC INTEGER
);
----------------第一部分测试数据
INSERT INTO TEST VALUES('A1', 2, 'C1', 'C1' ,        20,         123); 
INSERT INTO TEST VALUES('A1', 2, 'C1', 'C2' ,        30,         111); 
INSERT INTO TEST VALUES('A1', 2, 'C1', 'C2' ,        20,         222); 
INSERT INTO TEST VALUES('A1', 2, 'C1', 'C3' ,        10,         211); 
INSERT INTO TEST VALUES('A2', 3, 'C4', 'C1' ,        40,         321); 
INSERT INTO TEST VALUES('A2', 3, 'C4', 'C4' ,        50,         222); 
INSERT INTO TEST VALUES('A2', 3, 'C4', 'C4' ,        60,         333); 
INSERT INTO TEST VALUES('A2', 3, 'C4', 'C5' ,        70,         223);
COMMIT;
--select * from test;
---------------------------------------------------------------行转列的存储过程
CREATE OR REPLACE PROCEDURE P_TEST IS
  V_SQL VARCHAR2(2000);
  CURSOR CURSOR_1 IS SELECT DISTINCT T.XCLCK FROM TEST T ORDER BY XCLCK; 
    
    BEGIN
      V_SQL := 'SELECT WL,XYSL,XYCK';

      FOR V_XCLCK IN CURSOR_1
      LOOP
        V_SQL := V_SQL || ',' || 'SUM(DECODE(XCLCK,''' || V_XCLCK.XCLCK ||
                 ''',XCLCKSL,0)) AS ' || V_XCLCK.XCLCK;
      END LOOP;
      
      V_SQL := V_SQL || ' FROM TEST GROUP BY WL,XYSL,XYCK ORDER BY WL,XYSL,XYCK';
      --DBMS_OUTPUT.PUT_LINE(V_SQL);
      V_SQL := 'CREATE OR REPLACE VIEW RESULT  AS '||  V_SQL;
      --DBMS_OUTPUT.PUT_LINE(V_SQL);
      EXECUTE IMMEDIATE V_SQL;
    END;
----------------------------------------------------------------结果
----------------执行存储过程，生成视图
BEGIN
  P_TEST;               
END;
----------------结果
SELECT * FROM RESULT T;
WL                                            XYSL XYCK               C1         C2         C3         C4         C5
---------- --------------------------------------- ---------- ---------- ---------- ---------- ---------- ----------
A1                                               2 C1                 20         50         10          0          0
A2                                               3 C4                 40          0          0        110         70

----------------第二部分测试数据
INSERT INTO TEST VALUES('A1', 2, 'C1', 'C6' ,        20,         124); 
INSERT INTO TEST VALUES('A2', 2, 'C1', 'C7' ,        30,         121); 
INSERT INTO TEST VALUES('A3', 2, 'C1', 'C8' ,        20,         322); 
COMMIT;
----------------报告存储过程，生成视图
BEGIN
  P_TEST;               
END;
----------------结果
SELECT * FROM RESULT T;
WL     XYSL XYCK          C1       C2         C3         C4         C5         C6         C7         C8
----- ----- -------- ------- -------- ---------- ---------- ---------- ---------- ---------- ----------
A1        2 C1            20       50         10          0          0         20          0          0
A2        2 C1             0        0          0          0          0          0         30          0
A2        3 C4            40        0          0        110         70          0          0          0
A3        2 C1             0        0          0          0          0          0          0         20
--------------- 删除实体
DROP VIEW RESULT;
DROP PROCEDURE P_TEST;
DROP TABLE TEST;  

转自：https://www.cnblogs.com/QQParadise/articles/1712093.html